The ocean’s forage fish are worth $17 billion and deserve more credit and conservation
August 11, 2014
By Alex Card on August 11, 2014
Forage fish don’t get the credit they deserve, or so contends a study published in Fish and Fisheries. The tiny schooling fish such as herring, sardines and anchovies are often relegated to the role of culinary afterthought or fish meal for bigger, more profitable fish.
But the study shows that these swept-aside species are both vital to marine ecosystems and carry far greater economic value than is typically believed.
Calculations revealed that forage fish contribute $16.9 billion to global fisheries each year, amounting to 20 percent of global marine fisheries at-dock catch values. While forage fish catches bring in $5.6 billion, the fisheries they support as a food source are worth $11.3 billion.
These results were more significant than the researchers had imagined, said Konstantine Rountos a senior postdoctoral associate at Stony Brook University’s Institute for Ocean Conservation Science, and co-lead author.
“We went into it suspecting that forage fish had this important role as prey, but we didn’t know that it would be twice as much as their direct catch value,” Rountos said. But those values only represent a portion of the total economic worth of forage fish. Rountos noted that the study doesn’t factor in forage fishes’ contributions to recreational fisheries, or non-fishery uses.
Rountos became involved with the study as a doctoral student. There he worked under the auspices of the Lenfest Forage Fish Task Force, a panel of 13 preeminent marine and fisheries scientists convened by the institute and the Lenfest Ocean Program.
“I was tasked with helping the task force pursue a broad overview of the ecological and economic contributions that forage fish make,” Rountos said. “It was the first attempt to evaluate their role as prey in marine ecosystems on a global scale.”
The researchers examined three facets of forage fish species: their value in direct fishery catches, their roles as prey to other commercially fished species and as prey to non-fished marine predators such as seabirds, mammals and certain other fish. To determine this, the researchers compiled data from Ecopath models — mathematical models that simplify ecosystems into a standardized format.
“This was a synthesis of ecosystem or food web models that we compiled — 72 in total — from around the world,” Rountos said. Drawing from publicly available models, he said, “allows for greater transparency, and for people to replicate our study.”
Even more so than larger pelagic fish, forage fish are quite sensitive to physical and climatological forces. El Nino and La Nina cycles, climate change, ocean acidification and fishery exploitation all pose a threat to these vital members of marine ecosystems. The study, Rountos said, seeks to inform fishery managers about the value of forage fish so they can understand the trade-offs inherent to each method of use.
“Learning about the trade-offs can provide managers with information to manage forage fish in the most productive way,” Rountos said.
Read the article at FISHSENS Magazine